catalog-service/src/internal/worker/worker.go
2024-07-18 18:29:40 +02:00

162 lines
3.6 KiB
Go

package worker
import (
"fmt"
"log"
"os"
"os/signal"
"strconv"
"strings"
"syscall"
"github.com/go-redis/redis/v8"
"github.com/jackc/pgx/v5/pgxpool"
amqp "github.com/rabbitmq/amqp091-go"
"git.pbiernat.io/egommerce/go-api-pkg/consul"
"git.pbiernat.io/egommerce/go-api-pkg/fluentd"
"git.pbiernat.io/egommerce/go-api-pkg/rabbitmq"
"git.pbiernat.io/egommerce/catalog-service/internal/event"
cnf "git.pbiernat.io/egommerce/catalog-service/internal/server"
"git.pbiernat.io/egommerce/catalog-service/internal/service"
)
type (
Worker struct {
Config *cnf.Config
Cache *redis.Client
Database *pgxpool.Pool
Eventbus *amqp.Channel
Logger *fluentd.Logger
Registry *consul.Service
}
OptionFn func(*Worker) error // FIXME: similar in server/server.go
)
func New(c *cnf.Config, opts ...OptionFn) *Worker {
w := &Worker{
Config: c,
}
for _, opt := range opts {
if err := opt(w); err != nil {
log.Fatalf("Failed to attach extension to the worker. Err: %v\n", err)
}
}
return w
}
func (w *Worker) Start(while chan struct{}) error {
go func() {
sigint := make(chan os.Signal, 1)
signal.Notify(sigint, os.Interrupt, syscall.SIGINT, syscall.SIGTERM)
<-sigint
w.Shutdown()
close(while)
}()
run := w.createRunFile("./app.run") // TODO move to common library (shared between server and worker)
defer w.removeRunFile(run)
err := w.doWork()
if err != nil {
log.Fatalf("Failed to start worker: %s. Reason: %v\n", w.Config.Base.AppID, err)
close(while)
}
w.Logger.Log("Waiting for messages...")
return nil
}
func (w *Worker) Shutdown() error {
w.Logger.Log("Worker %s is going down...", w.Config.Base.AppID)
w.Registry.Unregister()
w.Eventbus.Close()
w.Database.Close()
w.Logger.Log("Gone.")
w.Logger.Close()
return nil
}
func (w *Worker) createRunFile(path string) *os.File {
run, err := os.Create(path)
if err != nil {
log.Fatalf("Failed to create run file. Reason: %v\n", err)
os.Exit(1)
}
run.WriteString(strconv.Itoa(os.Getpid()))
return run
}
func (w *Worker) removeRunFile(f *os.File) error {
return f.Close()
}
func (w *Worker) doWork() error {
msgs, err := w.Eventbus.Consume(
w.Config.EventBusQueue, // queue
"", // consumer
false, // auto-ack
false, // exclusive
false, // no-local
false, // no-wait
nil, // args
)
if err != nil {
w.Logger.Log("Failed to register a consumer: %s", err)
os.Exit(1)
}
go func() {
catalogSrvc := service.NewCatalogService(w.Database, w.Eventbus, w.Logger)
for d := range msgs {
go func(d amqp.Delivery) {
w.processMsg(catalogSrvc, d)
}(d)
}
}()
return nil
}
func (w *Worker) processMsg(srvc *service.CatalogService, d amqp.Delivery) {
msg, err := rabbitmq.Deserialize(d.Body)
if err != nil {
w.Logger.Log("Deserialization error: %v\n", err)
d.Reject(false)
return
}
name := fmt.Sprintf("%s", msg["event"])
data := (msg["data"]).(map[string]interface{})
// reqID := (data["request_id"]).(string) // FIXME Check input params!
w.Logger.Log("Processing message \"%s\" with data: %v\n", name, data)
var ok = false
switch true { // Refactor -> use case for polymorphism
case strings.Contains(name, event.EVENT_WAREHOUSE_STOCK_UPDATED):
w.Logger.Log("Event: %s", event.EVENT_WAREHOUSE_STOCK_UPDATED)
}
rnr := NewCommandRunner(data, srvc)
ok, _ = rnr.run(data)
if ok {
w.Logger.Log("Successful executed message \"%s\"\n", name)
d.Ack(false)
return
}
w.Logger.Log("Error processing \"%s\": %s (%v)", name, err.Error(), err)
d.Reject(false) // FIXME: or Nack(repeat until success - maybe message shoud know...?
}